PCB sources and degradation in sediments of Ashtabula River, Ohio, USA, determined from receptor models

İmamoğlu, İpek
Chrıstensen, Er
The PCB pollution in Ashtabula River sediments was evaluated using a factor analysis (FA) model with non-negative constraints, and a chemical mass balance (CMB) model The FA model identified Aroclor 1248 as the major PCB source, and also a congener pattern significantly different from that of any Aroclor The CMB model that uses linear combinations of Aroclors, failed to reproduce the sample congener profiles with good statistical fit The findings from both models indicate that the PCBs in Ashtabula River sediments have undergone significant alterations changing their profiles from those of the original sources These alterations may be explained by the anaerobic dechlorination of highly chlorinated congeners, according to dechlorination activities H/H.


PCB sources, transformations, and contributions in recent Fox River, Wisconsin sediments determined from receptor modeling
İmamoğlu, İpek (Elsevier BV, 2002-08-01)
The PCB contamination in lower Fox River sediments was investigated in order to identify possible PCB sources, contributions, and transformations, using two receptor models. Congener specific sediment PCB data from sites immediately upstream of DePere dam to Green Bay that had been gathered for the Green Bay/Fox River Mass Balance Study, were used in this analysis. The first receptor model is a self training factor analysis (FA) model with non-negative constraints that was applied to identify the PCB source...
Parallel preconditioning techniques for numerical solution of three dimensional partial differential equations
Sivas, Abdullah Ali; Manguoğlu, Murat; Department of Scientific Computing (2016)
Partial differential equations are commonly used in industry and science to model observed phenomena and gain insight regarding phenomena or solve related problems. Recently three dimensional partial differential equations started to become more and more essential and popular. Numerical solution of these problems usually is composed of two steps; discretization with some scheme and solving resulting sparse linear system which is large and usually ill-conditioned. Large size encourages usage of iterative sol...
Numerical simulation of radiating flows
Karaismail, Ertan; Selçuk, Nevin; Department of Chemical Engineering (2005)
Predictive accuracy of the previously developed coupled code for the solution of the time-dependent Navier-Stokes equations in conjunction with the radiative transfer equation was first assessed by applying it to the prediction of thermally radiating, hydrodynamically developed laminar pipe flow for which the numerical solution had been reported in the literature. The effect of radiation on flow and temperature fields was demonstrated for different values of conduction to radiation ratio. It was found that ...
Epoxidation of Propylene on a [Ag14O9] Cluster Representing Ag2O (001) Surface: A Density Functional Theory Study
Fellah, Mehmet Ferdi; Önal, Işık (2012-01-01)
Density functional theory calculations were employed to study partial oxidation of propylene on a [Ag14O9] cluster representing Ag2O (001) surface for which positive effect for ethylene oxide formation has been reported in our earlier work at the same level of theory (Fellah et al., Catal Lett 141: 762, 2011). Propylene oxide (PO), propanal, acetone and G-allyl radical formation reaction mechanisms were investigated. P-allyl formation path and two propylene adsorption paths resulting in PO formation are com...
Raman bandwidths calculated for the librational ( a -phase) and internal (8, d loc and d phases) modes in solid N 2 using pseudospin-phonon coupling (PS) and energy-fluctuation (EF) models
Yurtseven, Hasan Hamit (Elsevier BV, 2020-10-01)
This study gives the calculation of the Raman bandwidths using the models of the pseudospin-phonon coupling (PS) and energy fluctuation (EF) where the Raman frequency calculated from the molecular field theory, is considered as the order parameter close to the phase transitions in nitrogen. In particular, we study the temperature dependence of the Raman bandwidths and frequency shifts of the Eg librational mode (zero pressure) and the internal modes of and (at various pressures) for the solid nitrogen by ...
Citation Formats
İ. İmamoğlu and E. Chrıstensen, “PCB sources and degradation in sediments of Ashtabula River, Ohio, USA, determined from receptor models,” WATER SCIENCE AND TECHNOLOGY, pp. 89–96, 2002, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/53947.